Vegetation Treatments Using Herbicides on BLM Lands in Oregon
Draft Environmental Impact Statement
October 2009
Draft EIS and Proposed Action
The Bureau of Land Management (BLM) currently uses herbicides selectively and
conservatively in combination with other treatment methods, such as mechanical or
manual removal of vegetation and biological control, to control and manage the spread of
noxious weeds.
The BLM has prepared a Draft Environmental Impact Statement (EIS) that analyzes a
proposal to make additional herbicides available to BLM Districts in Oregon for:
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control of noxious and other invasive weeds;
control of native vegetation encroaching on rights-of-way, administrative sites, and
recreation sites;
control of native vegetation when needed to control pests in state-identified pest
quarantine areas, and;
implementing wildlife habitat improvement projects to benefit BLM sensitive and
Federally-listed wildlife species.
Under the Proposed Action (Alternative Number 4) in the Draft EIS, the BLM anticipates
annually treating approximately 28,100 acres of invasive plants using non-herbicide
methods (mechanical, manual and biocontrol) and 30,300 acres of invasive plants using
herbicides.
The BLM also anticipates treating 15,100 acres of native plants using herbicides in such
areas as rights-of-way, recreation sites and administrative sites and to meet habitat
objectives for listed wildlife species.
The BLM currently treats approximately 2,500 acres of noxious weeds using mechanical
methods, 2,000 acres using manual removal, 1,500 acres using biocontrol methods, and
12,000 acres using herbicides.
Need for the Proposed Action
As a result of 1984 and 1987 U.S. District Court orders, the BLM in Oregon only utilizes
four of the 18 herbicides currently utilized by the rest of the Bureau in other western
states and only uses those herbicides in the treatment of noxious weeds.
Although the BLM has an aggressive noxious weed control program that includes
prevention measures as well as manual, mechanical and herbicide treatments, noxious
weeds are spreading on BLM lands in Oregon at an estimated 12 percent per year, or
144,000 acres per year.
The use of the additional herbicides would allow for more effective treatment of
noxious and invasive vegetation. Currently there are 12 listed noxious weed species
(such as medusahead rye) that cannot be effectively treated using existing manual,
mechanical or herbicide treatment methods nor are there effective controls for the
1
invasive species such as cheatgrass which, like medusahead, is an annual grass. These
weeds are overtaking native sagebrush ecosystems, infesting habitat of Federally-listed
plant and animal species, and increasing the risk of wildfire.
The herbicides being analyzed in the Draft EIS are being considered for use because of
their effectiveness and because they can be used in smaller doses, are more targetspecific, and are less likely to adversely affect people and other non-target organisms
such as fish and wildlife than the four herbicides currently available to the BLM in Oregon.
While it isn’t possible under any alternative in this EIS to eliminate noxious and invasive
weeds, the proposed action is expected to slow the noxious weed spread rate from its
current 12 percent per year to 6 percent per year.
Proposed Action - Additional Details
In addition to treating approximately 30,300 acres of invasive plants using herbicides, the
Proposed Action would also make herbicides available for the treatment of native
vegetation in rights-of-way, administrative sites, and recreation sites. The use of
herbicides in combination or as a replacement of current manual and mechanical
treatment methods is estimated to save the BLM approximately $1 million per year. This
type of treatment would occur on approximately 15,100 acres per year.
The proposed action also proposes to use herbicides to treat native vegetation in those
instances where it will benefit BLM sensitive and Federally-listed wildlife species. These
types of projects would total approximately 5,000 acres per year. An example would be
the use of herbicides to improve habitat conditions for Sage-grouse by treating juniper
trees that are encroaching on sagebrush habitat in eastern Oregon.
Vegetation types and the occurrence of invasive species differ across the state.
Therefore, the proposed action would make 12 herbicides available to Districts west of
the Cascades and 16 herbicides available to Districts east of the Cascades
(See Table 3-1 for a description of the herbicides).
The Proposed Action would prohibit aerial application of herbicides west of the Cascades.
The BLM manages approximately 26 percent of the lands in Oregon and the proposed
use of herbicides on 30,300 acres is very small in comparison to statewide herbicide use.
In an effort to put BLM’s proposed herbicide use in context, following is a table that
displays use of the 18 herbicides analyzed in the Draft EIS and the use of those
herbicides across Oregon in 2008 (See Table 4-1 below). The Oregon-wide use figures
are from the State of Oregon Department of Agriculture’s annual Oregon Pesticide Use
Reporting System and do not include household use.
Definitions
Invasive plants (or weeds) are non-native aggressive plants with the potential to cause
significant damage to native ecosystems and/ or cause significant economic losses.
Noxious weeds are a subset of invasive plants that are county, state, or Federallylisted as injurious to public health, agriculture, recreation, wildlife, or any public or
private property.
2
Vegetation includes noxious weeds, invasive weeds, and introduced and native plants.
Native vegetation includes native and desirable non-native plants.
Biological control – The use of non-native agents including invertebrate parasites and
predators (usually insects, mites, and nematodes), and plant pathogens to reduce
populations of invasive plants.
Please See Tables 3-1 and 4-1 on the Following Pages
3
42
Table 3-1. Herbicide Information
Herbicide
Representative
Trade Names1
2, 4-D
Many, including
Amine, Hardball,
Unison, Saber, Salvo,
Aqua-Kleen, and
Platoon
Bromacil
Hyvar
Chlorsulfuron
Telar
Clopyralid
Transline, Stinger,
Spur
Dicamba
Vanquish, Banvel,
Diablo, Vision,
Clarity
Diflufenzopyr +
Dicamba
Overdrive, Distinct
Pre/post
Emergent
Common Targets
Annual and biennial
broadleaf weeds.Kochia,
white top, perennial
pepperweed, Russian thistle
and knapweed, sagebrush,
rabbitbrush.
Annual grasses and
broadleaf weeds.Cheatgrass,
puncturevine, ragweed, wild
oat, dandelion, quackgrass,
wild carrot.
Thistles, wild carrot, giant
horsetail, poison hemlock,
Russian knapweed, marestail,
perennial pepperweed,
puncturevine, tansy ragwort,
common tansy, common
teasel,dalmation toadflax,
yellow toadflax, whitetop,
dyers woad
Thistles, common burdock,
knapweeds, yellow
starthistle, oxeye daisy,
hawkweeds, prickly lettuce,
dandelion, cutleaf teasel,
kudzu, buffalobur
Knapweeds, kochia, and
thistles.
Knapweeds, kochia, and
thistles.
Types of BLM
Selective to
Point of
Lands Where Use
Plant Types Application is Permitted2
broadleaf
no
broadleaf
broadleaf
broadleaf,
woody
plants
broadleaf
Diflufenzopyr
Diquat
Reward
Giant salvinia, hydrilla, and
watermilfoils.
Diuron
Direx, Karmex
Annual grasses (including
bluegrass) and broadleaf
weeds.Lambsquarters,
kochia and Russian thistle.
annual
weeds, some
perennials
Fluridone
Avast!, Sonar
Hydrilla and watermilfoils
submersed
plants
Glyphosate
Many, including
Rodeo, Mirage,
Roundup Pro, and
Honcho
Grasses (including Italian
ryegrass), sedges, broadleaf
weeds, and woody shrubs.
no
no
Post
Foliar
Rng For RAq
OGM ROW R&C
1.9
4
12
0.047
0.141
Rng For
OGM ROW R&C
0.35
1
Rng
OGMROW R&C
0.25
2
0.2625
0.35
OGM ROW R&C
Pre and early
post
Rng
OGM ROW R&C
Soil or foliar
Post
Foliar
Pre and post
Foliar
Post
Foliar
Post
Aquatic
Rng
OGM ROW R&C
RAq
Pre
Soil
Post
Aquatic
Post
Soil or foliar
Typical Max3
1
Pre and post
Soil
Available
under
Alternative4
Application Rate
(lbs/acre)
OGM ROW R&C
RAq
Rng For RAq
OGM ROW R&C
1
4
6
20
0.15
1.3
2
7
2
√
√
√
3
4
5
Aerial
Spray5
Allowed
Koc6
SPISP II Rating8 (Leaching
Potential)
PARP11
PSRP10
Adsorbed
Solubility7 PLP9
Solution Particle
(mg/l)
Leaching Runoff
Runoff
20-100
33,900
Intermediate
Intermediate
Low
32
700
High
High
Intermediate
√
40
7,000
High
High
Intermediate
√
√
2
1,000
High
Intermediate
Low
√
√
no
2
400,000
High
Intermediate
Low
√
no
no
87
5,850
Low
Intermediate
Low
√
no
1,000,000
718,000
Very Low
Low
High
√
√
avoid
480
42
Intermediate
High
Intermediate
√
√
√
1,000
10
Low
Intermediate
Intermediate
√
√
√
24,000
900,000
Very Low
High
High
√
√
√
E
√
E
E
√
√
avoid
Herbicide
Representative
Trade Names1
Pre/post
Emergent
Application Rate
(lbs/acre)
Available
under
Alternative4
SPISP II Rating8 (Leaching
Potential)
PARP11
PSRP10
Adsorbed
Solubility7 PLP9
Solution Particle
(mg/l)
Leaching Runoff
Runoff
Types of BLM
Aerial
Selective to
Point of
Lands Where Use
Spray5
Common Targets
Plant Types Application is Permitted2
Typical Max3
2 3 4 5
Allowed
Koc6
grasses,
Annual and perennial grasses
Pre and post
Hexazinone
broadleaf,
Rng For
Interand broadleaf weeds, brush,
1
8
√ √ √
54
33,000
High
High
Velpar
woody
OGM ROW R&C
mediate
and trees.
Soil or foliar
plants
Cheatgrass, leafy spurge,
some
Pre and post
Imazapic
Rng For
Intermedusahead, white top,
broadleaf
0.0313 0.1875
√ √ √
137
2,200
High
High
Plateau, Panoramic
OGM ROW R&C
mediate
dalmation toadflax and
and grasses
Soil
Russian knapweed.
Annual and perennial
Imazapyr
Pre and post
broadleaf weeds, brush, trees.
Rng For RAq
InterArsenal, Stalker,
no
0.45
1.5
√ √ √
100
>11,000
High
High
Saltcedar, Russian olive,
OGM ROW R&C
mediate
Habitat, Polaris
Soil or foliar
tanoak
Whitetop, perennial
Metsulfuron methyl
broadleaf,
Post
Rng For
Interpepperweed and other
Escort, Patriot,
woody
0.03
0.15
√ √ √
35
9,500
High
High
OGM ROW R&C
mediate
mustards and biennial
PureStand
plants
Soil or foliar
thistles.
Perennial and woody species.
Knapweeds, starthistle,
Picloram
broadleaf,
Pre and post
thistle, bindweed,leafy
Rng For
InterTriumph, OutPost,
woody
0.4
1
√ √ √ √
16
200,000
High
High
spurge, rabbitbrush, rush
OGM ROW R&C
mediate
Tordon
plants
Foliar
skeletonweed, and poison
oak.
Pre and post
Downy brome, annual and
Sulfometuron methyl
For
Interno
0.14
0.38
E E √
no
78
70
High
Low
perennial mustards, and
Oust, Spyder
OGM ROW R&C
mediate
Soil or foliar
medusahead.
broadleaf,
Pre and post
Tebuthiuron
Rng
InterCreosotebush and sagebrush
woody
0.5
4
E √
80
2,500
High
High
Spike
OGM ROW R&C
mediate
(thinning).
plants
Soil
Triclopyr
broadleaf,
Post
Saltcedar, purple loosestrife,
Rng For RAq
20 (salt)
InterGarlon, Renovate,
woody
1
10
√ √ √
435
High
High
Canada thistle, tanoak,
OGM ROW R&C
780 (ester)
mediate
Element
plants
Foliar
Himalayan blackberry
1
See Appendix 9 (Herbicides) for the full list of herbicide trade names allowed for use on BLM Lands in Oregon, including formulations with 2 or more active ingredients.
2
Rng = Rangeland
For = Forest Land
RAq = Riparian or Aquatic
OGM = Oils, Gas, and Mineral Sites
ROW = Rights-of-Way
R&C = Recreation and Cultural Sites
3
Shading denotes herbicides that are limited, by PEIS Mitigation Measures, to typical application rates, where feasible.The maximum application rate for these herbicides is shown for informational purposes.
4
√ indicates herbicides that would be available statewide; E indicates herbicides that would be available only to districts east of the Cascades.
5
Aerial spray not allowed for any districts west of the Cascades under Alternatives 3 and 4.
6
Koc: Soil organic carbon sorption coefficient of an active ingredient in mL/g.For a given chemical, the greater the Koc value, the less soluble the chemical is in water and the higher affinity the chemical has for soil
organic carbon.For most chemicals, a higher affinity for soil organic carbon (greater Koc) results in less mobility in soil.
7
Solubility indirectly relates to runoff potential, if solubility number is low runoff potential is high
8
SPISP II = Soil Pesticide Interaction Screening Procedure version II, which is a NRCS model that calculates leaching potential from basic soil properties (USDA 1994b).
9
PLP - Pesticide Leaching Potential indicates the tendency of a pesticide to move in solution with water and leach below the root zone.A low rating indicates minimal movement and no need for mitigation.PLP is
calculated according to a WIN-PST algorithm, and then the resulting rating is adjusted for type of spraying being conducted.
10
PSRP - Pesticide Solution Runoff Potential indicates the tendency of a pesticide to move in surface runoff in the solution phase.A rating as calculated according to a WIN-PST algorithm indicates the potential for
pesticide loss in solution runoff.Ratings are adjusted according to type of spraying being conducted.
11
PARP - Pesticide Adsorbed Runoff Potential indicates the tendency of a pesticide to move in surface runoff attached to soil particles.A rating as calculated according to a WIN-PST algorithm indicates potential for
pesticide movement adsorbed to sediment.Ratings are adjusted according to type of spraying being conducted.
Data source: USDA 2006b
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Vegetation Treatments Using Herbicides on BLM Lands in Oregon
Table 4-1. 2008 Oregon-Wide Use of the 18 Herbicides Analyzed in this EIS and Comparison with BLM
Proposed Action (Alternative 4)
Herbicide and rank1
2. Glyphosate
7. 2,4-D
13. Diuron
25. Triclopyr
31. Hexazinone
34. Dicamba
50. Clopyralid
59. Imazapyr
83. Sulfometuron methyl
99. Bromacil
Picloram
Metsulfuron-methyl
Diquat
Chlorsulfuron
Tebuthiuron
Imazapic
Fluridone
Diflufenzopyr + Dicamba
1
2
Lbs Reported by ODA
Assumed Acres
Statewide2
1,914,144
778,878
385,174
125,542
105,284
96,964
48,592
29,859
16,866
11,189
5,891
5,252
2,334
2,006
720
314
22
No data
957,072
778,878
64,196
125,542
105,284
387,856
138,833
66,354
120,470
2,797
14,727
175,059
2,334
42,685
1,441
10,023
143
No Data
Est. Acres under Alt 4 on
BLM Lands
4,200
5,700
800
3,900
400
1,700
2,300
2,500
1,200
700
3,400
3,300
0
4,100
100
14,100
300
0
% of OR acres that BLM
Proposed Usage Would
Represent
0.44%
0.73%
1.25%
3.11%
0.38%
0.44%
1.66%
3.77%
1.00%
25.02%
23.09%
1.89%
0%
9.61%
6.94%
140.68%
209.20%
0%
Rank is only known for the herbicides included in ODA’s list of 100 most used Pesticides
Reported pounds divided by the BLM typical application rate.
acres if the typical rate3 is assumed (ODA 2009b). Table 4-1 shows the reported pounds in Oregon for herbicides
included in this EIS. Included are their numerical rank in the Oregon report in terms of pounds applied (if they
were in the 100 most-used pesticides), and equivalent acres calculated from the BLM typical application rate and,
for comparison purposes, the estimated acres of the same herbicide expected to be applied by the BLM under the
proposed action and its percent of the 2008 Oregon total. (The BLM manages about 26 percent of the lands in
Oregon.) Agricultural uses are included in the Oregon totals; the table does not attempt to compare like uses.
NCAP-NMFS Settlement Agreement to Examine 37 Pesticides
In July 2008, a settlement was reached in NW Coalition for Alternatives to Pesticides et al. v. NMFS. The
settlement requires the National Marine Fisheries Service to both examine the impacts of 37 pesticides on
protected salmon and steelhead, and to design measures that will minimize adverse impacts. The EPA had
previously identified these 37 pesticides as potentially harmful to these anadromous fish. Among the pesticides
included in this settlement are three used or proposed for use by the BLM: 2,4-D, diuron, and triclopyr BEE (a
form of triclopyr). The BLM would comply with any mitigation and SOPs that result from these studies, which
could include a ban on any or all of these herbicides. Table 4-1 indicates that BLM’s use of 2,4-D, diuron, and
triclopyr would account for about 0.73, 1.25, and 3.11 percent of the total use in the State respectively, and BLM’s
SOPs and PEIS Mitigation Measures limit effects to non-target species. BLM proposed use is not likely to
substantially contribute to anadromous fish effects.
3 Typical application rates for each herbicide are shown on Table 3-4.
90